Directions

In a medium bowl, whisk together flour, baking powder, and salt; set aside.

In stand mixer with paddle attachment (starting on low), cream together room temperature butter and sugar on medium-high until light and fluffy. Reduce speed to low and add in eggs, one at a time and mix until just blended.

Add in vanilla, 2 tablespoons of lemon juice and milk and mix for about 30 seconds on low. Slowly add in dry ingredients and mix until just combined.

Remove from mixer then fold in lemon zest with spatula.
Divide batter evenly among prepared muffin cups. Transfer muffin tin to oven and bake until tops are just dry to the touch, [timer length=18]18[/timer] – [timer length=20]20 minutes[/timer].
Use pastry brush to brush remaining 1 tablespoon of lemon juice over the top of the cupcake.

Place butter, vanilla and jam in stand mixer with whisk attachment. Whisk on medium-high for 1-2 minutes, or until fully incorporated.

With mixer on low, add in sugar, one cup at a time. When mixer starts to struggle, drizzle in milk one tablespoon at a time.
After all milk as been added whisk buttercream on high for 1-2 minutes.
To make cupcakes, put buttercream in a pastry bag with a large open tip. (or no tip at all, just the opening of the bag) and pipe out dollops on top of cooled cupcake.